By default, if you stop touching your iPhone screen, the display will automatically dim and then lock itself after exactly 30 seconds. While this aggressive auto-lock feature is fantastic for preserving battery life and securing your personal data, it can be incredibly frustrating if you are trying to read a long recipe while cooking, or following a complex set of instructions without constantly tapping the screen to keep it awake.
Fortunately, you are not stuck with the 30-second default. iOS allows you to easily extend this timer, or disable the auto-lock feature entirely so the screen remains on forever.
How to Change the Auto-Lock Timer
The setting is located in the display preferences, not the security settings.
- Open the Settings app on your iPhone.
- Scroll down and tap on Display & Brightness.
- Scroll down until you find the setting labelled Auto-Lock. (It will currently say “30 Seconds” next to it). Tap it.
- You will be presented with a list of time intervals ranging from 30 seconds up to 5 minutes, plus an option for “Never.”
- Tap the new time limit you prefer (e.g., 3 Minutes) so a blue checkmark appears next to it.
You can now exit the settings app. Your screen will now wait a full three minutes before automatically locking itself.
Why is Auto-Lock Greyed Out?
Sometimes, users navigate to the Display & Brightness menu only to find that the Auto-Lock setting is completely greyed out and locked at 30 seconds, preventing them from tapping it.
This happens for one specific reason: Low Power Mode is active.
When you turn on Low Power Mode to save battery (indicated by the battery icon turning yellow), Apple strictly enforces the 30-second Auto-Lock limit to ensure your screen isn’t wasting precious energy. You cannot change the Auto-Lock timer while in this mode.
To fix this and regain access to the setting:
- Go back to the main Settings menu.
- Scroll down and tap on Battery.
- Toggle Low Power Mode to the OFF position.
Once disabled, you can return to the Display & Brightness menu, and the Auto-Lock setting will be clickable once again.
The Danger of “Never”
Choosing the “Never” option means your iPhone screen will stay on indefinitely until you physically press the power button to lock it.
While useful if you are using your phone as a bedside clock or a permanent dashboard, using “Never” in your daily life is dangerous. If you set your phone down in a coffee shop, the screen will never turn off, allowing anyone to walk past, pick up the phone, and access all your emails, photos, and messages without needing your passcode.